Laminated reactor



w. F. KOUBEK LAMINATED REACTOR Jam m 11950) Filed April 1946 INVENTOR, mm FT 1W.

Patented Jan. 10, 1950 LAMINATED REACTOR William F. Koubek, Cuba, N. Y., assignor, by mesne assignments, to Acme Electric Corporation, a corporation of New York Application April 6, 1946, Serial No. 660,092

2 Claims. 1

My invention relates to a perforated nonmagnetic air gap spacer and a bonding material between the cores of a reactor 01' other flux conducting structures to join the laminated cores together and thereby prevent excessive noise and audible humming.

In many applications where A. C. reactors are used, it is desirable to incorporate an air gap in the magnetic circuit in order to provide relatively constant inductance regardless of the change of flux density either on an average basis or on an instantaneous basis. When such an air gap is provided, particularly in the case of a laminated core, serious difliculty is encountered with audible hum and noise set up by the vibration of the separate laminated cores.

One of the objects of my invention is to reduce the noise level of this audible hum set up by the vibration of the separate laminated cores in the reactor by binding the laminated cores together with a bonding material which adheres to the abutting edges of the laminated cores.

Another object of my invention is the provision of a bonding material adhering to the abutting edge portions of laminated cores for joining the cores together in a flux conducting struc-' ture.

A further object of my invention is the provision of a flux conducting structur having a perforated spacer between the laminated cores in the flux conducting structure and a bondin material adhering to the edge portions of these laminated cores and extending through the openings in the perforated spacer.

Other objects and a fuller understanding of my invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawing, in which:

Figure 1 of my drawings represents a reactor in which my invention may be incorporated;

Figure 2 is an exploded view of Figure 1 to better illustrate the perforated air gap spacer; and

Figure 3 is an enlarged fragmentary crosssectional view taken along the line 8-3 of Figure 1.

Many diiferent methods have been tried with the aim in mind of reducing to a minimum the audible hum or noise level of reactors. I accomplish a reduction in noise level by incorporating in the air gap space a perforated spacer and a bonding material which adheres to the abutting edges of the laminated cores and extends through the openings in the perforated spacer. Throughshaped out my description I use the perforated air gap spacer and the bonding material in connection with a reactor. The term reactor is being used in a very broad sense to include transformers,

chokes, or any other electrical device having a flux conducting structure. The reactor, as herein described for the purpose of defining my invention, comprises generally a flux conducting structure In and a coil of wire M. This coil of wire I I, shown symbolically in Figure l of my drawing, may be of any suitable design and connected by electrical means to an electrical circuit.

.As is best illustrated in Figures 1 and 2, the flux conducting structure [0 includes an E- laminated core I 3 and an I-shaped laminated core l4. The E-shaped laminated core has end legs l5 and a center leg #6 terminated in end portions I1 and Hi respectively. The I- shaped laminated core M has an abutting edge portion l9 spaced from the end portions l5 and I6 of the E-shaped laminated core by a perforated non-magnetic air gap spacer 20. Nonmagnetic strap means 2| are fastened to the E-shaped laminated core [3 and the I-shaped laminated core [4 by bolts 22 or other suitable means to fasten the cores together to form a flux conducting structure Iii.

The perforated spacer 2!! may be constructed of any suitable material such, for example, as

paper, fibers, or other non-magnetic or nonferrous material. The purpose of the spacer is to regulate the distance between the laminated cores and thereby provide an air gap of th desired size in the magnetic circuit of the flux conducting structure. This perforated spacer 20 has openings or perforations 23, illustrated in Figure 2 as having circular cross section. However, the design and shape of these openings or perforations 23 in the perforated spacer 20 is immaterial and slight changes from the preferred design illustrated in my drawings may be 'made without departing from the scope of my invention.

The ends of the individual laminations 2-5 of the E-shaped laminated core I3, which constitute the end portions I! and I8 and the edges of the individual laminations 2B of the I-shaped laminated core M are joined together by a bonding material 21. As is best illustrated in Figure 3, this bonding material 21 has a joining portion 28 thereof which extends through the perforations 23 in the perforated spacer 20. The thickness of the adhering portion 29, of the bonding material 21 between the perforated spacer 20 and the abutting edge portions l8 and IQ of the laminated cores l4 and I6, is greatly exaggerated in Figure 3. Actually the total distance between the abutting edge portions [8 and I 9 of the laminated cores is substantially equal to the thickness of the perforated spacer 20.

As previously set forth, the bonding material 21 is employed to bind together the individual laminations of the=laminated cores; and also to bind together the laminated cores. In actual practice,

I have found that shellacs, varnishes, and other similar composition used in the art of manufacturing electrical appliances, are satisfactory as a.

bonding material for the binding operation. Also,

I have found that natural and synthetic rubbers. and rosins of a thermo-setting nature,-o1"natural' or synthetic products of a polymerizing or copolymerizing nature are satisfactory. It is understood, that the bonding material used may be selected for particular circumstances, and that any material which canbe placed on the laminatedcore abutting edges in a fluid orv plastic condition, and thereafter caused to harden. into a binding mass by evaporation, thermo setting, polymerizing ortcopolymerizing will serve the purpose of thebonding material.

The bonding material 21 joins together the ends of the individual laminations in the laminated core. Thejoining portion 28 of the bonding material 21, or that portion which extends through the openings orperforations. 23 of the.

perforated spacer 20 binds the abutting edge portions of the-laminated cores. together.

The use of theperforated air gap spacer between the laminated cores permits'the bond" betweenthelaminated cores by'the bonding material as well. as the bond between the individual laminations in these laminated cores, and also provides a non-magnetic gap therebetween. This bonding of the laminationsand laminated cores.

greatly reduces the audible hum set up: by the vibration of the-separate-laminated cores.

Although I have describedmy invention in its preferredformwith a certain degreeof particularity, it is understood that. the present disclosure of the preferred form has been made only byway of example and that numerous changes in the details of construction and'the combination and.

arrangement of parts may be resortedto without departingfrom the spirit and the scope of the invention as hereinafter claimed;

. I-shaped laminations, and a vibration dampening bonding non-magnetic material extending through the perforations in the spacer and adhering to the end edge of each of the legs of each of the E-shaped laminations and also adhering to theside edge of each of the I-shaped laminations.

2." Alaminated reactor comprising, a plurality of magnetic laminations disposed to form a pair of laminatedicores, each of said magnetic laminations having an edge with the edges of the magnetic laminations. in one, core' facing the edges of the magnetic laminations in' the other of the pair of: cores, anon-magnetic perforated spacer separating the edge of each of the laminatlons of one core from theredge of each. of the laminations of the other core; anda vibration dampening bonding non-magnetic material extending through the perforations in the spacer and adhering-to the edge of each of the laminations of each of the cores.

WILLIAM F. KOUBEK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name a Date 1,420,989 Fondiller June 27, 1922 2,293,951 Seastone et al Aug. 25, 1942 2,312,140 Welch, Jr Feb. 23, 1943 2,318,095 Putman- May 4, 1943 2,320,922 Ford June 1, 1943 2,367,591 McAllister Jan. 16, 1945 2,372,074 Ford Mar. 20, 1945 

